Proton exchange membrane fuel cells (PEMFCs) have aroused great interest in recent years, in particular for transportation applications. However, fuel cell (FC) technology is not yet ready for large-scale commercial use, as it requires more understanding and intensive development, in particular in the thermal behavior area. Such understanding of the FC requires many large-scale simulations that can take unacceptably large execution time. This is especially true when using traditional models that are governed by heat equations and based on computational tools that derive approximate solutions to partial differential equations. Such multimodel systems also require synchronization that results in overhead. Instead, in this paper, a new fully integrated modeling approach that lends itself to parallelism is introduced. This approach can benefit from advances in parallel computing, and thus dramatically reduce time and enable multiple large simulations. This is called the global nodal method, which is intended to analyze and simulate the thermal behavior of PEMFCs. Parallel simulations are implemented with the message passing interface (MPI) and using the unified parallel C (UPC) language on parallel systems. It will be shown that computation time to conduct thermal behavior in large-scale simulation using MPI and UPC is significantly reduced compared to sequential simulations, and obtained data are highly precise and accurate.